1. Field of the Invention
This invention is in the field of dental floss holders where a small segment or strand of dental floss is secured between two spaced apart arms which extend from a handle which include dental flossers which are essentially flat, dental flossers having the flosser head bent relative to the handle, and dental flossers having a replaceable flosser head.
RELATED INVENTIONSU.S. Pat. No.InventorDate4,006,750I. S. ChodorowFeb. 8, 19774,016,892I. S. ChodorowFeb. 8, 1977D 244,376I. S. ChodorowMay 1977D 250,214I. S. ChodorowNov. 7, 1978D 301,071R. FranchiMay 9, 19895,086,792I. S. ChodorowFeb. 11, 19925,538,023I. S. ChodorowJul. 23, 19965,829,458I. S. ChodorowNov. 3, 19986,065,479I. S. ChodorowMay 23, 2000
2. Prior Art
Dental flossing devices, also known as dental flossers and dental floss holders, are now popular in the market and are manufactured in both disposable and non-disposable configurations. While some of these dental flossers are relatively large and contain in their handles a spool of floss which is unrolled periodically to provide a new segment of floss spanning the spaced apart fingers, other dental flossers are generally flat for ease of packaging and for ease and convenience of carrying in one's pocket. These flossers are also inexpensive, are promoted as disposable, and have a segment of floss permanently embedded in and spanning a pair of arms.
Prior art flossers have often been made using styrene for the handles and Nylon for the dental floss. In the manufacture of such flossers, the highly stretchable Nylon floss is positioned in the mold and tensioned before injection of the fluid plastic to form the handle. Subsequently, when the plastic cools, the arms of each flosser tend to shrink inwardly toward each other, thereby reducing tension in the strand of floss. Since the Nylon floss is stretched a greater amount than handle shrinkage, the Nylon floss remains stretched and relatively taut even after the shrinkage of the arms toward each other.
Some flossers use fiber such as multi-filament ultra high molecular weight polyethylene (UHMWP) which stretches very little. When handles for these flossers cool after injection molding and the arms shrink inwardly, the UHMWP floss does not have the large pre-stretch of Nylon floss, and consequently, the floss between the arms becomes slack.
The prior art includes various handles designed to remove slack that develops during use when the floss stretches, including Applicant's prior U.S. Pat. No. 5,692,531 which discloses various configurations of finger or trigger-type projections that extend from the handle and cause divergence of the arms to which the floss is attached.
Also known is a two-component device comprising a handle and a separate flosser head with slack floss, where the flosser head is fully separable from the handle. When the flosser head is attached to the handle a latch element both spreads the arms of the flosser head slightly and removably secures the flosser head to the handle. These flosser heads are replaceable, while the handle is retained and used repeatedly. This flosser solves the slack problem prior to use, but introduces a variety of disadvantages. First, this device requires the are promoted as disposable, and have a segment of floss permanently embedded in and spanning a pair of arms.
Prior art flossers have often been made using styrene for the handles and Nylon for the dental floss. In the manufacture of such flossers, the highly stretchable Nylon floss is positioned in the mold and tensioned before injection of the fluid plastic to form the handle. Subsequently, when the plastic cools, the arms of each flosser tend to shrink inwardly toward each other, thereby reducing tension in the strand of floss. Since the Nylon floss is stretched a greater amount than handle shrinkage, the Nylon floss remains stretched and relatively taut even after the shrinkage of the arms toward each other.
Some flossers use fiber such as multi-filament ultra high molecular weight polyethylene (UHMWP) which stretches very little. When handles for these flossers cool after injection molding and the arms shrink inwardly, the UHMWP floss does not have the large pre-stretch of Nylon floss, and consequently, the floss between the arms becomes slack.
The prior art includes various handles designed to remove slack that develops during use when the floss stretches, including Applicant's prior U.S. Pat. No. 5,692,531 which discloses various configurations of finger or trigger-type projections that extend from the handle and cause divergence of the arms to which the floss is attached.
Also known is a two-component device comprising a handle and a separate flosser head with slack floss, where the flosser head is fully separable from the handle. When the flosser head is attached to the handle a latch element both spreads the arms of the flosser head slightly and removably secures the flosser head to the handle. These flosser heads are replaceable, while the handle is retained and used repeatedly. This flosser solves the slack problem prior to use, but introduces a variety of disadvantages. First, this device requires the user to retain the handle; thus, the user must either carry the handle with him/her or leave it at home and use the flosser only at home. Second, the user has the inconvenience of assembling and disassembling the components. Third, the overall device is relatively large, and the two parts require separate molds and separate manufacturing phases, all being more expensive. Fourth, the floss head can disengage in the mouth and become a swallowing or choking hazard.